PS vs. Thermoset PI
PS belongs to the thermoplastics classification, while thermoset PI belongs to the thermoset plastics. There are 19 material properties with values for both materials. Properties with values for just one material (11, in this case) are not shown.
For each property being compared, the top bar is PS and the bottom bar is thermoset PI.
Metric UnitsUS Customary Units
Mechanical Properties
| Elongation at Break, % | 1.8 to 40 | |
| 2.0 to 5.9 |
| Flexural Strength, MPa | 62 to 80 | |
| 60 to 100 |
| Impact Strength: Notched Izod, J/m | 19 to 45 | |
| 21 to 43 |
| Tensile Strength: Ultimate (UTS), MPa | 32 to 44 | |
| 37 to 81 |
Thermal Properties
| Glass Transition Temperature, °C | 100 | |
| 360 |
| Maximum Temperature: Autoignition, °C | 360 to 420 | |
| 380 |
| Maximum Temperature: Decomposition, °C | 320 to 330 | |
| 330 |
| Maximum Temperature: Mechanical, °C | 70 | |
| 260 |
| Specific Heat Capacity, J/kg-K | 1250 to 1400 | |
| 1130 |
| Thermal Conductivity, W/m-K | 0.14 to 0.22 | |
| 0.29 to 1.7 |
| Thermal Expansion, µm/m-K | 80 to 98 | |
| 38 to 54 |
Electrical Properties
| Dielectric Strength (Breakdown Potential), kV/mm | 18 to 20 | |
| 20 |
| Electrical Resistivity Order of Magnitude, 10x Ω-m | 14 to 15 | |
| 15 |
Otherwise Unclassified Properties
| Density, g/cm3 | 1.0 | |
| 1.4 to 1.6 |
| Limiting Oxygen Index (LOI), % | 18 | |
| 40 |
| Water Absorption After 24 Hours, % | 0.040 to 0.080 | |
| 0.14 to 0.24 |
Common Calculations
| Strength to Weight: Axial, points | 8.5 to 12 | |
| 6.5 to 16 |
| Strength to Weight: Bending, points | 22 to 26 | |
| 16 to 30 |
| Thermal Diffusivity, mm2/s | 0.11 to 0.15 | |
| 0.18 to 0.95 |